Relationship between cathepsin-D and other prognostic factors in human breast cancer

Cathepsin-D (CATH-D) is a lysosomal protease induced by estrogens in estrogen receptor-positive breast cancer call lines and constitutively produced by estrogen receptor-negative breast cancer cells. The concentration of CATH-D in the cytosol of 97 human breast tumor tissues was correlated with other well-known prognostic factors for human breast cancer. CATH-D was significantly higher in node-positive than in node-negative tumors (P = 0.042, Kruskal-Wallis test). However, no correlation was found between enzyme levels and the number of positive nodes. CATH-D concentration did not correlate with age, menopausal status, clinical stage of the disease, size of the primary tumor, steroid receptors, thymidine labeling index, histological grade, nuclear grade or cellularity. CATH-D did not show any association with the known prognostic factors evaluated in this study and its association with lymph nodes was only weak.